NPP4 is present on the vascular surfaces of human brain. To confirm the tissue localization of NPP4, we stained adult human brain with polyclonal rabbit anti-ENPP4 Ab (Proteintech Group), using Vector dylight 549 (red fluorescence Ab) to image. Strong staining was noted throughout the brain in all blood vessels, as demonstrated above in branched vessels, 2 examples of which are depicted in this figure. (Left column) Light contrast images of branched vessels. (Middle column) Red fluorescent channel of the identical field. (Right column) Overlay of DAPI channel (blue) with NPP4 protein (red). Note the strong highlighting of NPP4 in branched blood vessels and cross-sections of smaller vessels demonstrating NPP4 staining in the interior of the vessel.